From: Anirudh Rayabharam <[email protected]> Sent: Wednesday, February 11, 2026 9:07 AM > > Rename mshv_synic_init() to mshv_synic_cpu_init() and > mshv_synic_cleanup() to mshv_synic_cpu_exit() to better reflect that > these functions handle per-cpu synic setup and teardown. > > Use mshv_synic_init/cleanup() to perform init/cleanup that is not per-cpu. > Move all the synic related setup from mshv_parent_partition_init. > > Move the reboot notifier to mshv_synic.c because it currently only > operates on the synic cpuhp state. > > Move out synic_pages from the global mshv_root since it's use is now
s/it's/its/ > completely local to mshv_synic.c. > > This is in preparation for the next patch which will add more stuff to > mshv_synic_init(). > > No functional change. > > Signed-off-by: Anirudh Rayabharam (Microsoft) <[email protected]> > --- > drivers/hv/mshv_root.h | 5 ++- > drivers/hv/mshv_root_main.c | 59 +++++------------------------- > drivers/hv/mshv_synic.c | 71 +++++++++++++++++++++++++++++++++---- > 3 files changed, 75 insertions(+), 60 deletions(-) > > diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h > index 3c1d88b36741..26e0320c8097 100644 > --- a/drivers/hv/mshv_root.h > +++ b/drivers/hv/mshv_root.h > @@ -183,7 +183,6 @@ struct hv_synic_pages { > }; > > struct mshv_root { > - struct hv_synic_pages __percpu *synic_pages; > spinlock_t pt_ht_lock; > DECLARE_HASHTABLE(pt_htable, MSHV_PARTITIONS_HASH_BITS); > struct hv_partition_property_vmm_capabilities vmm_caps; > @@ -242,8 +241,8 @@ int mshv_register_doorbell(u64 partition_id, > doorbell_cb_t doorbell_cb, > void mshv_unregister_doorbell(u64 partition_id, int doorbell_portid); > > void mshv_isr(void); > -int mshv_synic_init(unsigned int cpu); > -int mshv_synic_cleanup(unsigned int cpu); > +int mshv_synic_init(struct device *dev); > +void mshv_synic_cleanup(void); > > static inline bool mshv_partition_encrypted(struct mshv_partition *partition) > { > diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c > index 681b58154d5e..7c1666456e78 100644 > --- a/drivers/hv/mshv_root_main.c > +++ b/drivers/hv/mshv_root_main.c > @@ -2035,7 +2035,6 @@ mshv_dev_release(struct inode *inode, struct file *filp) > return 0; > } > > -static int mshv_cpuhp_online; > static int mshv_root_sched_online; > > static const char *scheduler_type_to_string(enum hv_scheduler_type type) > @@ -2198,40 +2197,14 @@ root_scheduler_deinit(void) > free_percpu(root_scheduler_output); > } > > -static int mshv_reboot_notify(struct notifier_block *nb, > - unsigned long code, void *unused) > -{ > - cpuhp_remove_state(mshv_cpuhp_online); > - return 0; > -} > - > -struct notifier_block mshv_reboot_nb = { > - .notifier_call = mshv_reboot_notify, > -}; > - > static void mshv_root_partition_exit(void) > { > - unregister_reboot_notifier(&mshv_reboot_nb); > root_scheduler_deinit(); > } > > static int __init mshv_root_partition_init(struct device *dev) > { > - int err; > - > - err = root_scheduler_init(dev); > - if (err) > - return err; > - > - err = register_reboot_notifier(&mshv_reboot_nb); > - if (err) > - goto root_sched_deinit; > - > - return 0; > - > -root_sched_deinit: > - root_scheduler_deinit(); > - return err; > + return root_scheduler_init(dev); > } > > static void mshv_init_vmm_caps(struct device *dev) > @@ -2276,31 +2249,18 @@ static int __init mshv_parent_partition_init(void) > MSHV_HV_MAX_VERSION); > } > > - mshv_root.synic_pages = alloc_percpu(struct hv_synic_pages); > - if (!mshv_root.synic_pages) { > - dev_err(dev, "Failed to allocate percpu synic page\n"); > - ret = -ENOMEM; > + ret = mshv_synic_init(dev); > + if (ret) > goto device_deregister; > - } > - > - ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "mshv_synic", > - mshv_synic_init, > - mshv_synic_cleanup); > - if (ret < 0) { > - dev_err(dev, "Failed to setup cpu hotplug state: %i\n", ret); > - goto free_synic_pages; > - } > - > - mshv_cpuhp_online = ret; > > ret = mshv_retrieve_scheduler_type(dev); > if (ret) > - goto remove_cpu_state; > + goto synic_cleanup; > > if (hv_root_partition()) > ret = mshv_root_partition_init(dev); > if (ret) > - goto remove_cpu_state; > + goto synic_cleanup; > > mshv_init_vmm_caps(dev); > > @@ -2318,10 +2278,8 @@ static int __init mshv_parent_partition_init(void) > exit_partition: > if (hv_root_partition()) > mshv_root_partition_exit(); > -remove_cpu_state: > - cpuhp_remove_state(mshv_cpuhp_online); > -free_synic_pages: > - free_percpu(mshv_root.synic_pages); > +synic_cleanup: > + mshv_synic_cleanup(); > device_deregister: > misc_deregister(&mshv_dev); > return ret; > @@ -2335,8 +2293,7 @@ static void __exit mshv_parent_partition_exit(void) > mshv_irqfd_wq_cleanup(); > if (hv_root_partition()) > mshv_root_partition_exit(); > - cpuhp_remove_state(mshv_cpuhp_online); > - free_percpu(mshv_root.synic_pages); > + mshv_synic_cleanup(); > } > > module_init(mshv_parent_partition_init); > diff --git a/drivers/hv/mshv_synic.c b/drivers/hv/mshv_synic.c > index f8b0337cdc82..074e37c48876 100644 > --- a/drivers/hv/mshv_synic.c > +++ b/drivers/hv/mshv_synic.c > @@ -12,11 +12,16 @@ > #include <linux/mm.h> > #include <linux/io.h> > #include <linux/random.h> > +#include <linux/cpuhotplug.h> > +#include <linux/reboot.h> > #include <asm/mshyperv.h> > > #include "mshv_eventfd.h" > #include "mshv.h" > > +static int synic_cpuhp_online; > +static struct hv_synic_pages __percpu *synic_pages; > + > static u32 synic_event_ring_get_queued_port(u32 sint_index) > { > struct hv_synic_event_ring_page **event_ring_page; > @@ -26,7 +31,7 @@ static u32 synic_event_ring_get_queued_port(u32 sint_index) > u32 message; > u8 tail; > > - spages = this_cpu_ptr(mshv_root.synic_pages); > + spages = this_cpu_ptr(synic_pages); > event_ring_page = &spages->synic_event_ring_page; > synic_eventring_tail = (u8 **)this_cpu_ptr(hv_synic_eventring_tail); > > @@ -393,7 +398,7 @@ mshv_intercept_isr(struct hv_message *msg) > > void mshv_isr(void) > { > - struct hv_synic_pages *spages = this_cpu_ptr(mshv_root.synic_pages); > + struct hv_synic_pages *spages = this_cpu_ptr(synic_pages); > struct hv_message_page **msg_page = &spages->hyp_synic_message_page; > struct hv_message *msg; > bool handled; > @@ -446,7 +451,7 @@ void mshv_isr(void) > } > } > > -int mshv_synic_init(unsigned int cpu) > +static int mshv_synic_cpu_init(unsigned int cpu) > { > union hv_synic_simp simp; > union hv_synic_siefp siefp; > @@ -455,7 +460,7 @@ int mshv_synic_init(unsigned int cpu) > union hv_synic_sint sint; > #endif > union hv_synic_scontrol sctrl; > - struct hv_synic_pages *spages = this_cpu_ptr(mshv_root.synic_pages); > + struct hv_synic_pages *spages = this_cpu_ptr(synic_pages); > struct hv_message_page **msg_page = &spages->hyp_synic_message_page; > struct hv_synic_event_flags_page **event_flags_page = > &spages->synic_event_flags_page; > @@ -542,14 +547,14 @@ int mshv_synic_init(unsigned int cpu) > return -EFAULT; > } > > -int mshv_synic_cleanup(unsigned int cpu) > +static int mshv_synic_cpu_exit(unsigned int cpu) > { > union hv_synic_sint sint; > union hv_synic_simp simp; > union hv_synic_siefp siefp; > union hv_synic_sirbp sirbp; > union hv_synic_scontrol sctrl; > - struct hv_synic_pages *spages = this_cpu_ptr(mshv_root.synic_pages); > + struct hv_synic_pages *spages = this_cpu_ptr(synic_pages); > struct hv_message_page **msg_page = &spages->hyp_synic_message_page; > struct hv_synic_event_flags_page **event_flags_page = > &spages->synic_event_flags_page; > @@ -663,3 +668,57 @@ mshv_unregister_doorbell(u64 partition_id, int > doorbell_portid) > > mshv_portid_free(doorbell_portid); > } > + > +static int mshv_synic_reboot_notify(struct notifier_block *nb, > + unsigned long code, void *unused) > +{ > + if (!hv_root_partition()) > + return 0; I'm curious as to why the synic is cleaned up only for the root partition, but not for L1VH parents. L1VH parents *do* cleanup their synic in mshv_parent_partition_exit(). I probably don't understand all the vagaries of L1VH parents .... > + > + cpuhp_remove_state(synic_cpuhp_online); > + return 0; > +} > + > +static struct notifier_block mshv_synic_reboot_nb = { > + .notifier_call = mshv_synic_reboot_notify, > +}; > + > +int __init mshv_synic_init(struct device *dev) > +{ > + int ret = 0; > + > + synic_pages = alloc_percpu(struct hv_synic_pages); > + if (!synic_pages) { > + dev_err(dev, "Failed to allocate percpu synic page\n"); > + return -ENOMEM; > + } > + > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "mshv_synic", > + mshv_synic_cpu_init, > + mshv_synic_cpu_exit); > + if (ret < 0) { > + dev_err(dev, "Failed to setup cpu hotplug state: %i\n", ret); > + goto free_synic_pages; > + } > + > + synic_cpuhp_online = ret; > + > + ret = register_reboot_notifier(&mshv_synic_reboot_nb); > + if (ret) > + goto remove_cpuhp_state; > + > + return 0; > + > +remove_cpuhp_state: > + cpuhp_remove_state(synic_cpuhp_online); > +free_synic_pages: > + free_percpu(synic_pages); > + return ret; > +} > + > +void mshv_synic_cleanup(void) > +{ > + unregister_reboot_notifier(&mshv_synic_reboot_nb); > + cpuhp_remove_state(synic_cpuhp_online); > + free_percpu(synic_pages); > +} > -- > 2.34.1 >
